code: def test_graph_simple(self):
      plugin = self.load_plugin([_RUN_WITH_GRAPH_WITH_METADATA])
      graph = self._get_graph(
          plugin,
          tag=None,
          is_conceptual=False,
          experiment="eid",
      )
      node_names = set(node.name for node in graph.node)
      self.assertEqual(
          {
              "k1",
              "k2",
              "pow",
              "sub",
              "expected",
              "sub_1",
              "error",
              "message_prefix",
              "error_string",
              "error_message",
              "summary_message",
              "summary_message/tag",
              "summary_message/serialized_summary_metadata",
          },
          node_names,
      )
  
imports: import collections.abc
  import math
  import os.path
  import tensorflow
  from google.protobuf import text_format
  from tensorboard import context
  from tensorboard import errors
  from tensorboard.backend.event_processing import data_provider
  from tensorboard.backend.event_processing import plugin_event_multiplexer
  from tensorboard.compat.proto import config_pb2
  from tensorboard.plugins import base_plugin
  from tensorboard.plugins.graph import graphs_plugin
  from tensorboard.util import test_util
label_desc: Use image node_id 4 for calling the GraphsPluginV1Test obj's underlying member method code with example usage: obj.test_graph_simple() without return types